252 SYMBIOSIS OF PHANEROGAMS AND FUNGI. 



Special importance is given to the social life by the fact that the chief species of 

 Phanerogams partic'pating in it are of gregarious growth and cover whole tracts of 

 country, forming boundless heaths and measureless forests, as, for instance, the 

 various heaths, the oak, the beech, the fir, and the poplar. The conception of this 

 subterranean life affecting every moorland and vast timbered tract is one full of 

 wonder and interest. 



We can now see why it is that the ground in woods is the abode of such a 

 profusion of fungi. No doubt some of these fungi draw their nutriment exclusively 

 from the store of dead plant-organs accumulated there; but others, as certainly, are 

 in social connection with the living roots of green-leaved plants. It is true we 

 cannot yet state precisely what are the species of fungi which contract this sort of 

 union, or whether generally a definite elective affinity exists between certain fungi 

 and certain green-leaved plants. There is much in favour of this supposition in 

 a few cases: but, on the other hand, it is very unlikely that each of the various 

 Phanerogams occupying a limited area of ground in a pine-forest, where a few 

 square meters of earth contain so many tangled roots belonging to pines, spurge 

 laurels, bilberries, cranberries, heath, and winter-green, that they can only be 

 separated with difficulty, should select from the great host of fungi growing in the 

 forest a different partner. In instances of this kind it seems just to suppose that 

 the mycelium of one and the same species of fungus enters simultaneously into 

 connection with all or several of the plants growing close together; it is similarly 

 probable that the mycelia of different species of fungi render to one and the same 

 flowering-plant the service of absorption according to the locality in which it occurs. 

 This surmise is supported by the fact that when certain species, brought from distant 

 parts and regularly exhibiting mycelial mantles on the ends of their roots, are 

 reared in our gardens and greenhouses from seed, they unite in these abodes with 

 fungus-mycelia, which certainly do not exist in the regions where the Phanerogams 

 in question grow wild. Thus, for instance, the roots of the Japanese tree, Sophora 

 Japonica, and those of the Epacrideae of Australia, are found in European gardens 

 in social union with fungi, which with us are native, but which certainly do not 

 occur in Japan or Australia; and it is therefore scarcely open to doubt that the 

 Sophora Japonica, to take one example, associates itself with different fungi in 

 different regions. 



Now that the symbiosis of fungi devoid of chlorophyll with green-leaved 

 Phanerogams has been discussed, we are for the first time in a position to deal with 

 that most remarkable of all cases of food-absorption wherein the subterranean roots 

 of a flowering-plant are completely wrapped in a mycelial mantle, whilst the parts 

 which shoot up above ground bear no green leaves, and, in general, possess no trace 

 of chlorophyll. Such is the case of Monotropa, the various species of which are 

 intimately allied in the structure of flowers and fruit with the Primrose and Winter- 

 green, and are met with scattered everywhere in shady woods. Their stems, which 

 are from 10 to 20 centimeters in height and emerge from the mould of the forest- 

 ground in summer time, are thick, fleshy, succulent, and profusely beset with 



